﻿#region License

// Dimebrain TweetSharp
// (www.dimebrain.com)
// 
// The MIT License
// 
// Copyright (c) 2009 Dimebrain
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
// 

#endregion

using System;
using System.Collections.Generic;

namespace Dimebrain.TweetSharp.Core.Caching
{
    /// <summary>
    /// A basic in-memory cache.
    /// </summary>
    internal class SimpleCache : IClientCache
    {
        private const string NOT_SUPPORTED_MESSAGE = "This simple cache does not support expiration.";

        private static readonly IDictionary<string, object> _cache = new Dictionary<string, object>(0);

        #region IWebCache Members

        public int Count
        {
            get { return _cache.Count; }
        }

        public void Insert(string key, object value)
        {
            if (!_cache.ContainsKey(key))
            {
                _cache.Add(key, value);
            }
            else
            {
                _cache[key] = value;
            }
        }

        public void Insert(string key, object value, DateTime absoluteExpiration)
        {
            throw new NotSupportedException(NOT_SUPPORTED_MESSAGE);
        }

        public void Insert(string key, object value, TimeSpan slidingExpiration)
        {
            throw new NotSupportedException(NOT_SUPPORTED_MESSAGE);
        }

        public T Get<T>(string key)
        {
            if (_cache.ContainsKey(key))
            {
                return (T) _cache[key];
            }
            return default(T);
        }

        public void Remove(string key)
        {
            if (_cache.ContainsKey(key))
            {
                _cache.Remove(key);
            }
        }

        public IEnumerable<string> Keys
        {
            get { return _cache.Keys; }
        }

        #endregion
    }
}